In which information, either audio or video, is encoded in a non quantitized variable, as opposed to digital signals which are prevalent today.

Aspect Ratio

Variance of a television’s screen’s width in relation to its height, the new standard being a 16:9 ratio since the switch to digital and HDTV. Other standards include 4:3 and 21:9.



Communication in which interaction between parties does not take place simultaneously. Professors record the lecture first, then students watch it at a later time.


The information carrying capacity of a communications channel or line referring to both the speed and quality. Digital Bandwidth is measured in bits per second. (BPs).




Frequency range from approximately 4 to 6 gigahertz (billion cycles per second) by communication satellites. The microwave frequencies of the C-band perform better under adverse weather conditions in comparison with the Ku Band. C Band is mostly used for satellite communications transmissions, some Wi-Fi devices, some cordless phones, and some weather radar systems


A codec converts analog video and audio signals into digital signals for transmission over digital circuits, and then converts the digital signal back to analog signals for display. A Codec is also capable of compressing the digital signals so more information can be sent at lower speeds. They are also known as Coder-Decoders.

Color Bars & tone

A standard signal used by the television industry for the alignment of cameras and videotape recordings accompanied by a continuous tone and color bars. quite often color bar are used as the test pattern before the start of a recording. It is also the same sound you hear when anything gets bleeped out on Television or Radio.

Compressed Video
Video signals are downsized to allow travel along a smaller carrier. Similar to a zip file on a computer, it makes it more manageable.


The process of reducing the amount of visual information sent in a signal by transmitting only changes in the video.

Control Room

A room separate from the studio in which the director, the technical director, the audio engineer, and sometimes the light technician perform the various production functions.


A communications format used with both electronic and light-based systems that transmits audio, video, and data as bits (O’s and I’s) of information. Codecs are used to convert analog to digital and back. Digital technology also allows communication signals to be compressed for more efficient transmission.


Either 1. The process of receiving a satellite transmission. 2. The antenna used to receive a satellite transmission. Other terms include “dish” or “earth station”.


An invisible boundary that separates networked computers, usually inside a company, business or household from outside sources. The computers inside the firewall have internal access to files and share content not shared outside the Firewall eg. a firewall protects the internal computers from the external computers.


File Transfer Protocol; a method for moving data electronically from one PC to another, usually across networks.

Full Duplex Mode

The ability to listen and speak at the same time during a video conference. think Skype.

IP Address

Internet Protocol address. the international standard for addressing and sending data via the internet. Each connecting site has their own number: usually


Instructional Television Fixed Service: a band of microwave frequencies set aside by the FCC, exclusively for the transmission of educational programming. Allows broadcast of audio, video, and data to receive sites located within twenty miles of the point of origination. Receive sites require a codec. Responsible in part for Distance Education Courses.


Inverse Multiplexer: an interface between the network and the codec. The IMUX combines  to a number of ISDN channels together into one high rate circuit, resulting in higher (kbps) speed connections.


Integrated Services Digital Network: the network for North America. its more efficient and allows users to run at both 64kbps or 56kbps.


1000 bits per second: the way to measure the speed at which voice, data, and video signals are transmitted. The higher the speed the better quality of the videoconferencing. If multiple people are on the video confrence Kbps usually get bumped down to the person with the lowest bandwidth and set the Kbps for all participants at the lowest common denominator.


Frequency range from approximately 11-14 GHz (billion cycles per second). most notably for fixed and broadcast services. Big government organizations such as NASA use Ku Band for tracking data relays, used for probes like the mars rover, Pluto’s New Horizon satellite, and even the international space station.


Multipoint Control Unit: The piece of equipment that bridges multiple video connections (sites) into one conference.

Microwave (communications usage)

High frequency radio waves used for point to point and omni-directional communication of audio, data and video signals. Microwave frequencies require direct line of sight to operate; obstructions such as trees of buildings distort the signal.


Any document that uses interactive forms of communication: interactive things such as blackboard, audio, streaming media, photographs and video etc.

Multipoint Conference

A video conference involving three or more locations. It is usually voice activated which means, whichever site is speaking is the site everyone else is able to see.


National Television Standards Committee: Standard for color television transmission used in the United States,Canada, Mexico, Japan, Venezuela, the Philippines, Burma, Chile and South Korea. The standard includes interlaced display with 60 fields per second, 29.97 frames per second.

Point-to-Point Conference

A video conference between only two locations.

Satellite (communications usage)

A man made spacecraft intended to orbit earth for the purpose of relaying & facilitating long-distance communication of voice, data and video.

Satellite Receiver

Component that is placed inside the classroom, auditorium, etc., and is user operated to select and tune satellite transponders.


A computer connected to a network that offers various services, such as document viewing or file transfers, to other computers called clients.


Communication in which interaction between parties is taking place simultaneously, as opposed to Asynchronous. A common example is when students attend a face to face class.


A permanent transmission link with a digital capacity of 1.544 Mbps. Typically divided into 24 channels of 64 Kbps each. The T-1 can be partitioned to support multiple application types.

Transponder (channel)

A device located on board the satellite which receives signals uplinked by a programmer and transmits then back to earth on a different frequency.


This is the inverse of a Downlink. Sending a transmission from the ground to a satellite.

Video Conferencing

Two-way, full motion, interactive digital communication that permits two ore more locations to engage in a face to face audio-visual interaction.


Voice Over Internet Protocol: A technology for transporting integrated digital voice, video and data over IP networks.